Long-term outcome of isolated mitral valve repair versus replacement for degenerative mitral regurgitation in propensity-matched patients

JTCVS Open. 2023 Dec 15:17:84-97. doi: 10.1016/j.xjon.2023.12.003. eCollection 2024 Feb.

Abstract

Objective: This study was performed to investigate the long-term outcomes in patients with degenerative mitral regurgitation (MR) undergoing mitral valve repair (MVr) versus mitral valve replacement (MVR) without concomitant surgeries.

Methods: The study cohort comprised 1493 patients with degenerative MR who were treated with isolated mitral valve surgery between January 2000 and December 2017 in a large multicenter (5 hospitals) registry of the Province of British Columbia, Canada, including 991 with repair and 502 with replacement. A propensity-matched comparison and risk-adjusted model were used to analyze the outcomes.

Results: After propensity matching (415 matched pairs), the 30-day mortalities were 2.4% and 3.6% in the MVr and MVR groups respectively (odds ratio [OR], 1.500; 95% confidence interval [CI], 0.674-3.339; P = .32). The MVR group had significantly greater rates of prolonged inotrope usage >24 hours (P = .024), prolonged ventilation (P = .039), and blood transfusion (P = .023). The respective 1-, 5-, 10-, and 15-year survival rates were 95.7%, 88.8%, 71.4%, and 53.3% in the MVr group, and 93.0%, 81.6%, 61.3%, and 46.0% in the MVR group (hazard ratio [HR], 1.355; 95% CI, 1.105-1.661; P = .004). A multivariable analysis revealed that MVR was an independent risk factor for 30-day mortality (OR, 2.270; 95% CI, 1.089-4.732; P = .029) and long-term mortality (HR, 1.417; 95% CI, 1.161-1.729; P < .001). The HR of MVR over MVr remained consistently greater than 1.0 across all ages.

Conclusions: MVr is associated with lower postoperative morbidity and better long-term survival compared with MVR in patients undergoing isolated mitral valve surgery for degenerative MR. The benefit of MVr appears age-independent.

Keywords: degenerative mitral valve disease; isolated mitral valve surgery; mitral valve repair; mitral valve replacement; propensity score matching.